#!/bin/sh

set -e

. /usr/share/pve-kernel-helper/scripts/functions


_get_partition_info() {
	if [ ! -e "$1" ]; then
		warn "E: '$1' does not exist!"
		exit 1
	fi
	bdev=$(realpath "$1")
	if [ ! -b "$bdev" ]; then
		warn "E: '$bdev' is not a block device!"
		exit 1
	fi

	bdev_info=$( \
	          lsblk \
	          --bytes \
	          --pairs \
	          -o 'UUID,SIZE,FSTYPE,PARTTYPE,PKNAME,MOUNTPOINT' \
	          "$bdev" \
	          )
	if [ -z "$bdev_info" ]; then
		warn "E: unable to get information about block device '$1'!"
		exit 1
	fi

	count=$(echo "$bdev_info" | grep -c '^')
	if [ "$count" -ne '1' ]; then
		echo "$bdev_info"
		warn "E: block device '$1' has children!"
		exit 1
	fi

	echo "$bdev_info"
	eval "$bdev_info"

	if [ -z "$PKNAME" ]; then
		warn "E: cannot determine parent device of '$1' - please provide a partition, not a full disk."
		exit 1
	fi

	if [ -n "$SIZE" ] && [ "$SIZE" -lt 268435456 ]; then
		warn "E: '$1' is too small (<256M)."
		exit 1
	fi

	if [ -n "$MOUNTPOINT" ]; then
		warn "E: '$1' is mounted on '$MOUNTPOINT' - exiting."
		exit 1
	fi
}

format() {
	part="$1"
	force="$2"

	_get_partition_info "$part"

	if [ -n "$FSTYPE" ]; then
		if [ -z "$force" ] || [ "$force" != '--force' ]; then
			warn "E: '$part' contains a filesystem ('$FSTYPE') - exiting (use --force to override)"
			exit 1
		fi
	fi

	part_basename=$(basename "$part")
	if [ -z "$part_basename" ]; then
		warn "E: unable to determine basename of '$part'"
		exit 1
	fi

	part_num=$(cat /sys/block/"$PKNAME"/"$part_basename"/partition)
	if [ -z "$part_num" ]; then
		warn "E: unable to determine partition number of '$part'"
		exit 1
	fi

	if [ -z "$PARTTYPE" ] || [ "$PARTTYPE" != "$ESPTYPE" ]; then
		echo "Setting partition type of '$part' to '$ESPTYPE'.."
		sgdisk "-t$part_num:$ESPTYPE" "/dev/$PKNAME"
		echo "Calling 'udevadm settle'.."
		udevadm settle --timeout=5
	fi

	echo "Formatting '$part' as vfat.."
	mkfs.vfat -F 32 "$part"
	echo "Done."
	exit 0
}

init() {
	part="$1"

	_get_partition_info "$part"

	if [ -z "$PARTTYPE" ] || [ "$PARTTYPE" != "$ESPTYPE" ]; then
		warn "E: '$part' has wrong partition type (!= $ESPTYPE)."
		exit 1
	fi

	if [ -z "$FSTYPE" ] || [ "$FSTYPE" != 'vfat' ]; then
		warn "E: '$part' has wrong filesystem (!= vfat)."
		exit 1
	fi

	if [ -z "$UUID" ]; then
		warn "E: '$part' has no UUID set, required for mounting."
		exit 1
	fi

	esp_mp="/var/tmp/espmounts/$UUID"

	mkdir -p "$esp_mp"
	echo "Mounting '$part' on '$esp_mp'."
	mount -t vfat "$part" "$esp_mp"

	echo "Installing systemd-boot.."
	mkdir -p "$esp_mp/$PMX_ESP_DIR"
	bootctl --path "$esp_mp" install

	echo "Configuring systemd-boot.."
	echo "timeout 3" > "$esp_mp/$PMX_LOADER_CONF.tmp"
	echo "default proxmox-*" >> "$esp_mp/$PMX_LOADER_CONF.tmp"
	mv "$esp_mp/$PMX_LOADER_CONF.tmp" "$esp_mp/$PMX_LOADER_CONF"
	echo "Unmounting '$part'."
	umount "$part"

	echo "Adding '$part' to list of synced ESPs.."
	if [ -e "$ESP_LIST" ]; then
		cp "$ESP_LIST" "$ESP_LIST.new"
	fi
	echo "$UUID" >> "$ESP_LIST.new"
	sort -uo "$ESP_LIST.new" "$ESP_LIST.new"
	mv "$ESP_LIST.new" "$ESP_LIST"

	echo "Refreshing kernels and initrds.."
	refresh
}

refresh() {
	hookscript='/etc/kernel/postinst.d/zz-pve-efiboot'
	echo "Running hook script '$hookscript'.."
	exec $hookscript
}

usage() {
	warn "USAGE: $0 <commands> [ARGS]"
	warn ""
	warn "       $0 format <partition> [--force]"
	warn "       $0 init <partition>"
	warn "       $0 refresh"
	warn "       $0 help"
}

help() {
	echo "USAGE: $0 format <partition> [--force]"
	echo ""
	echo "    format <partition> as EFI system partition. Use --force to format even if <partition> is currently in use."
	echo ""
	echo "USAGE: $0 init <partition>"
	echo ""
	echo "    initialize EFI system partition at <partition> for automatic synchronization of pve-kernels and their associated initrds."
	echo ""
	echo "USAGE: $0 refresh"
	echo ""
	echo "    refresh all configured EFI system partitions."
	echo ""
}

if [ -z "$1" ]; then
    usage
    exit 0
fi

case "$1" in
	'format')
		shift
		if [ -z "$1"  ]; then
			warn "E: <partition> is mandatory."
			warn ""
			usage
			exit 1
		fi
		format "$@"
		exit 0
	;;
	'init')
		reexec_in_mountns "$@"
		shift
		if [ -z "$1"  ]; then
			warn "E: <partition> is mandatory."
			warn ""
			usage
			exit 1
		fi
		init "$@"
		exit 0
	;;
	'refresh')
		shift
		refresh
		exit 0
	;;
	'help')
		shift
		help
		exit 0
	;;
	*)
		warn "Invalid/unknown command '$1'."
		warn ""
		usage
		exit 1
	;;
esac

exit 1